Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/85—Chromium, molybdenum or tungsten
  • B01J23/88—Molybdenum
  • B01J23/887—Molybdenum containing in addition other metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/8872—Alkali or alkaline earth metals
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/78—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with alkali- or alkaline earth metals
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/85—Chromium, molybdenum or tungsten
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/85—Chromium, molybdenum or tungsten
  • B01J23/88—Molybdenum
  • B01J23/887—Molybdenum containing in addition other metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/8871—Rare earth metals or actinides
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/889—Manganese, technetium or rhenium
  • B01J23/8898—Manganese, technetium or rhenium containing also molybdenum
• • B01J35/393—
• • B01J35/612—
• • B01J35/613—
• • B01J35/615—
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
  • C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
  • C01B3/06—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents
  • C01B3/12—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents by reaction of water vapour with carbon monoxide
  • C01B3/16—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents by reaction of water vapour with carbon monoxide using catalysts
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P20/00—Technologies relating to chemical industry
  • Y02P20/50—Improvements relating to the production of bulk chemicals
  • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

• This invention relates to the production of hydrogen by the reaction of steam with carbon monoxide in the presence of a catalyst. More specifically, this invention relates to the production of hydrogen and the conversion of carbon monoxide in sour gas streams, i.e., in synthesis gas mixtures containing sulfur-bearing impurities.
• the carbon monoxide reaction with steam has been known for many years as a method for producing hydrogen and C0 2 .
• Many catalytic materials have been proposed for use in the conversion of carbon monoxide with steam more commonly known as the water-gas shift process.
• U.S. Patent 417,068 disclosed that hydrogen could be obtained by passing carbon monoxide and steam over nickel or metallic cobalt spread on a refractory porous material such as pumice stone.
• Bosch and Wild in U.S. Patent 1,113,097, proposed that the cobalt constituent be supported on a refractory porous material.
• Larson in 1932, proposed in U.S. Patent 1,889,672, a catalyst comprising copper and various (group VI) metal oxides.
• CuO-ZnO reduced copper oxide-zinc oxide
• this gas is cooled to about 220°C to 277°C and the sulfur is removed by adsorption with a zinc oxide adsorbent and fed through a second catalytic converter utilizing a low temperature shift catalyst of the Dienes type at temperatures in the range of 204°C to 288°C.
• sulfactive catalyst comprising cobalt and the oxides and sulfides of molybdenum supported on relatively high surface area carriers. See, for example, British Patent 940,960, U.S. Patent 3,392,001 and U.S. Patent 3,529,939, all of which have been assigned to Badische Anilin & Soda-Fabrik A.G. (BASF). Aldridge, et.
• an alkali metal compound and a small percentage of an oxide of a fourth period metal including titanium, vanadium, chromium and manganese to the known sulfactive metal oxide catalyst constituents,for the carbon monoxide shift reaction produces a synergistic effect on catalyst activity.
• Oxides or sulfides of fourth period metals having atomic numbers of from 22-25 include titanium, vanadium, chromium and manganese.
• transition element listed in the groups Va, VIa and VIIa of the periodic system as used in the specification refers to the periodic system prepared and published by the Radio Corporation of America, includes the elements of vanadium, niobium, tantalum, chromium, molybdenum, tungsten, uranium, manganese and rhenium.
• the catalytic constituents have reasonably well defined themselves as oxides or sulfides of cobalt, nickel or molybdenum.
• Patents 3,850,840 and 3,850,841 the promotional effect of an alkali metal compound derived from an acid having an ionization constant less than 1 x 10 -3 in conjunction with the known sulfactive oxides and sulfides previously set forth.
• a fourth period metal such as manganese dioxide
• the stabilized alumina catalyst in which the gamma aluminum oxide was stabilized by the addition of small amounts of rare earth metal oxides had initial surface areas in the neighborhood of 125 to 150 m 2 /g with very little loss of surface area after use.
• the alumina had relatively high surface area identified as the gamma phase.
• the alumina was in the alpha phase and in some instances the x-ray diffraction showed both alpha and gamma phases in the catalyst.
• This catalyst is a cobalt molybdate on magnesium alumnate extrusions.
• the 3.2 mm extrusions had the following composition.
• This catalyst was a cobalt molybdate catalyst supported on alumina spheres.
• the surface area of this catalyst was 130 m 2 /g for the new catalyst and 74 m 2 /g for the used catalyst.
• Example 3 The spheres of Example 3 were impregnated by immersion into an aqueous solution of potassium carbonate. The catalyst was immersed and dried and immersed and dried until a concentration of 12 percent K 2 C0 3 was obtained. The catalyst was then calcined at a temperature of 427°C. This catalyst had an initial surface area measured by nitrogen absorption of 74 m 2 /g and a surface area in the used state of 70 m 2 /g.
• This preparation has magnesium aluminate spinel as the support.
• Magnesium aluminate spinel has both chemical and physical properties which are unique and which result in a support having high thermal resistance to the catalyst applied to the support migrating into the support interstitially.
• the magnesium aluminate support was prepared by mixing 28.3 parts MgO, 63.7 parts alpha alumina (10-15 m 2 /g surface area) and 8.0 parts alumina (acid reactive Boehmite type) with a nitric acid solution. After drying, granulating, and blending with a lubricant, the particles were compressed into tablets 4.8 mm in diameter and 3.2 mm in height. The tablets were then dried and calcined at 870°C and incorporated into a catalyst via solution impregnation and calcination for a nominal composition of 4 % C oO and 16 % MoO 3 .
• the analyzed product contained:
• the surface area of the new product measured by nitrogen absorption, was 7.8 m 2 /g and the surface area of the used product was 7 . 2 m 2 /g .
• the catalyst prepared in accordance with Example 5 in the form of 3.2 x 4.8 mm tablets were immersed in a solution of potassium carbonate and dried and reimmersed and dried for a sufficient time that the finished tablets contained 4 percent by weight of potassium carbonate K 2 C0 3 . These catalysts were then calcined at 427°C. These tablets had a nominal composition:
• the catalyst tablets prepared according to Example 5 were immersed into a solution of manganese nitrate. The immersed tablets were thereafter dried and calcined at 870°C for sufficient time to convert the manganese nitrate over to manganese dioxide (Mn0 2 ). These catalysts contained on analysis:
• the surface area was not run on the new catalyst but the used catalyst had a surface area as measured by nitrogen absorption of 3 .4 m 2 /g .
• Catalyst tablets prepared in accordance with Example 5 were immersed into a solution of potassium carbonate and dried and reimmersed and dried until 4 percent by weight of potassium carbonate was added to the catalyst by impregnation. This catalyst was then calcined at 427°C. The calcined catalyst was then immersed into an aqueous solution of manganese nitrate and the manganese nitrate impregnated catalyst was recalcined at 427°C to convert the manganese nitrate to manganese dioxide.
• the catalyst was impregnated by exact solution dipping. Multiple dips, therefore, are avoided to prevent dissolution of the K 2 C0 3 .
• the surface area of the catalyst after use was 6.6 m 2 /g. While surface area measurements were not run on the new catalyst, they were run on some other preparations of the same components and were in the range of 6.1 to 7. 8 m 2 /g in the new state, again, as measured by nitrogen absorption.
• the catalyst spheres prepared according to Example 4 were immersed by exact dipping into a solution of manganese nitrate so as to incorporate 1 % by weight manganese dioxide (expressed as the oxide) onto the catalyst.
• the catalyst was thereafter dried and calcined at 427°C to convert the nitrate to the oxide.
• This catalyst had a surface area in the new state as measured by nitrogen absorption of 175 m 2 /g and in the used state of 140 m 2 /g.
• the composition was as follows: X-ray diffraction measurement of the used catalyst showed both gamma and alpha phases of alumina.
• Another catalyst was prepared by the same method as described in Example 8, except that the potassium carbonate concentration was increased from 4 percent to 10 percent.
• the manganese dioxide concentration remained the same.
• the composition of the new catalyst was as follows:
• the catalyst of this example was again prepared in the same manner as Example 10 except that the manganese dioxide concentration was increased from 1 percent to 2 percent.
• the composition of the new catalyst by analysis was:
• This catalyst was prepared in the same method of Example 9 except that the potassium carbonate concentration was decreased to 10 percent and the manganese dioxide increased to 2 percent.
• the nominal composition of this catalyst was:
• This catalyst was prepared by the same method as Example 12 except that the potassium carbonate concentration was reduced to 4 percent and the manganese dioxide remained at the 2 percent level.
• the catalyst support in this case was magnesium aluminate, prepared in the method described in Example '5 except that the MgA1 2 0 4 carrier was calcined at 650°C rather than 870°C.
• the calcined tablets were then immersed into a cobalt-molybdenum ammine solution and dried. This procedure was repeated a sufficient number of times so that the cobalt oxide concentration was about 4 percent and the molybdenum oxide concentration was about 16 percent. Thereafter, the catalyst was dried and calcined and after cooling was then immersed into a potassium carbonate solution and dried to impregnate onto the catalyst 10 percent by weight of potassium carbonate.
• This catalyst was then calcined and cooled and manganese nitrate impregnated thereon by exact dipping to obtain 1 percent MnO 2 .
• the catalyst was again calcined to convert the manganese nitrate to the oxide at a concentration of about 1 percent.
• the surface area of the new catalyst, as measured by nitrogen absorption, was 69 m 2 /g, whereas the surface area of the used catalyst was in the neighborhood of 7 m 2 /g.
• the nominal composition was as follows:
• This catalyst was prepared identically to that of Example 14, except for omission of the final impregnation of the catalyst in the manganese nitrate solution. As a consequence, the catalyst contained no manganese dioxide but was otherwise identical. The surface area of the new catalyst was 65.0 m 2 /g and the used catalyst was 4.3 m 2 /g.
• the catalyst of this example was prepared by the same method as that of catalyst 12 except that only 1 percent of manganese dioxide was impregnated onto the catalyst rather than 2 percent.
• the surface area of the new catalyst was 190 m /g and surface area of the used catalyst was 10 7 m 2 /g.
• All the alumina in the new catalyst was in the gamma phase.
• the alumina of the used catalyst was found to be in both the alpha phases and the gamma phase.
• the catalyst of Example 2 was immersed into a solution of potassium carbonate and calcined a sufficient number of times to impregnate 10 percent by weight of potassium carbonate thereon. This catalyst was then immersed only once into a manganese nitrate solution to add 1.0 percent of manganese dioxide to the finished catalyst by exact dipping. During calcination at a temperature of 427°C, the manganese nitrate was converted to manganese dioxide.
• Alumina tablets consisting of gamma alumina in the form of 3.2 x 4.8 mm tablets, were immersed into a cobalt-molybdenum ammine solution of such concentration to add about 4.0 percent cobalt oxide and 16 percent molybdenum oxide to the catalyst.
• the metal salts were converted over to metal oxides.
• the calcined catalyst was immersed in a potassium carbonate solution.
• the catalyst then containing 10 percent by weight of potassium carbonate was calcined at 427°C and the calcined and cooled catalyst was then immersed once in a manganese nitrate solution so that 1 percent by weight of manganese expressed as the oxide was added by exact dipping.
• This catalyst was again calcined at 427 o C.
• the physical properties of the finished catalyst showed that the new catalyst had a surface area of 124 m 2 /g as measured by nitrogen absorption whereas the finished catalyst had a surface area of 24 m 2 /g.
• X-ray diffraction measurements of the new catalyst showed that the alumina existed both in the gamma and the alpha phase.
• the catalyst prepared in accordance with Example 2 was immersed in a solution of potassium carbonate. This procedure was continued with intermittent drying steps until the potassium carbonate concentration reached 10 percent. Thereafter, the catalyst was calcined at 427°C. The calcined and cooled catalyst was then immersed into a manganese nitrate solution to impregnate onto the catalyst 1 percent by weight expressed as the oxide of manganese and the catalyst was then calcined at 427 0 C as previously described. The surface area of this catalyst was 122 m 2 /g in the new state. The catalyst contained gamma alumina.
• This catalyst was prepared identically to the method of 16.
• the finished catalyst contained the following:
• the surface area of the new catalyst was 86 m 2 /g and of the used catalyst, 45 m 2 /g.
• X-ray diffraction indicated that the alumina existed in the alpha phase in both the new and used catalyst.
• the R size of the alumina was about 2000.
• the used catalyst also contained molybdenum sulfide (MoS 2 ), having an R size of 164.
• Example 9 the doubly promoted potassium carbonate/ manganese oxide catalyst shown in Example 9 was chosen as the standard. Thus, it was assigned a relative activity of 100 and all the other catalysts were measured in relation to this catalyst.
• catalyst 9 which is the cobalt oxide-molybdenum oxide on alumina promoted with 12 percent potassium carbonate and 1 percent manganese oxide, had a relative activity of 100 while the same composition of cobalt, molybdenum on the magnesium aluminate spinel catalyst had a relative activity of 101.
• the potassium concentration of catalyst 8 was only 4 % as compared to 12 %.
• the relative activity of catalyst 8 was 128, versus 100 for the standard catalyst.
• the relative activity was 135 to 100.
• catalyst 8 was operating at equilibrium.
• the catalyst of Example 7 had the same composition as the catalyst of Example 8 except for the omission of potassium carbonate.
• This catalyst (Example 7) had a relative activity of only 21 at 232°C, 25 at 288 0 C and 24 at 343°C.
• manganese dioxide to the standard cobalt molybdenum catalyst supported on the magnesium aluminate spinel without the alkali metal component promoter had no appreciable promotional effect on the catalyst.
• Example 6 Reffering to Example 6, in which this catalyst has the same composition as Example 8, but without the manganese oxide, the relative activity of the catalyst of Example 6 was only 38 at 232°C, 17 at 288°C, and 19 at 343°C.
• This catalyst in other words, had slightly less activity than the commercial catalyst, of Example 2, which was also unpromoted.
• the beneficial effect of potassium carbonate is clearly shown in the Example 4 in which 12 percent potassium carbonate showed a 65 relative activity at 232°C.and a 47 percent relative activity at 343°C. Nevertheless, even though the beneficial effect of the spinel carriers and the beneficial effects of the potassium carbonate promoters are clearly demonstrated, the beneficial effect of the double promotion is 1 to 2 times that of the individual constituents.
• Example 10 in which the identical composition was maintained on the magnesium aluminate carrier, the addition of an additional 1 percent Mn° 2 in Example 11 to raise that constituent from 1 percent to 2 percent did not increase the activity, and, in fact, decreased it slightly.
• the relative activity of Example 10 as can be seen at 232°C was 56.8, whereas the activity of Example 11 was 46.6.
• the same catalyst containing 2 percent manganese dioxide and 10 percent potassium carbonate in Example 12 had an activity of 48.9. Reducing the potassium carbonate from 10 percent to 4 percent, in Example 13, however, reduced the relative activity down to 16.6.
• That catalyst of Example 14 showed an extremely good relative activity of 99.4.
• This catalyst was supported on the magnesium aluminate spinel, but was calcined at 650°C rather than 870°C as had been the case with Examples 10 and 11. Omitting the manganese oxide constituent in Example 15 resulted in an activity of 69.5 as compared to 99.4 for Example 14.
• Example 19 both of these preparations contained essentially the same composition on alumina and each had high relative activities.
• the relative activity of Example 19 was 86.4 and 100 for the catalyst of Example 20. (Reference standard for Table II).
• the addition of potassium compounds has a promotional effect upon the sulfactive metal oxide catalyst.
• Supporting the sulfactive oxides on specific carriers, as for example, magnesium aluminate spinels, zinc aluminate spinels, and alumina also appears to enhance the activity of the catalyst.
• the sulfactive metal oxide components comprise cobalt oxide, cobalt sulfide, nickel sulfide, nickel oxide, in combination with an oxide of a transition element of groups V through VII and sulfides of the transition elements of groups V through VII of the periodic system of elements.

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• 1981
  • 1981-04-14 US US06/253,941 patent/US4389335A/en not_active Expired - Lifetime
• 1982
  • 1982-03-17 JP JP57040934A patent/JPS57171438A/ja active Granted
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